Entity Framework in Visual Studio: database is not created with DbContext base constructor

I'm brand new to Visual Studio and .NET, and I'm following this tutorial on Lynda (Code-first development with the Entity Framework) to create an ASP.NET MVC app where I should be able to add Tour objects to a database using a form.

I've created a class

MyDbContext

that inherits from

DbContext

.

I've added a base class constructor with the name of the database that needs to be created for this app when information is submitted from the form. I've also added a

Following with the debugger, when I try to add a new tour, it skips over the

SaveChanges

line and goes directly into the catch block. No database is ever created, and nothing shows up under App_Data in the Solution Explorer.

The tutorial mentions that the database will be created using SQL Server Express LocalDB, but I don't see any reference to LocalDB in the Server Explorer. This is still new, so I'm a little lost on how to approach this.

Thing is, when you use DbContext's contructor with a string parameter, the parameter must be either
1. name of a connection string from your app.config or web.config in the form name=MyConnectionString. For instance, your config contains